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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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All sourcesNASA NTRSDOE OSTI
DOE OSTI2019

AP-105 Melter Offgas Condensate and EMF Evaporator Concentrate Raman and LIBS Qualitative Evaluation for the use of In-Line Monitoring (Rev. 0)

The Pacific Northwest National Laboratory (PNNL) was tasked to perform Raman spectroscopy and laser induced breakdown spectroscopy (LIBS) testing on the melter off-gas condensate generated during low-activity waste process testing of a sample from Hanford Site tank AP-105 and/or evaporate from evaporation of the condensate. This was a proof-of-principle demonstration that Raman spectroscopy and LIBS have the potential to be used as analytical tools for in-line process analysis of key aqueous phase analytes in radioactive process streams associated with the Hanford Waste Treatment and Immobilization Plant. The work completed under this project complements work completed for WRPS with the development of in-line monitoring systems to characterize and quantify constituents of tank waste following Cs removal and filtration. The WRPS work is currently limited to Raman sensors and utilizes chemometric models for quantification of several anionic species in the sample system. It should be noted that while this approach can be applied to off-gas condensate streams, new chemometric models are needed to accurately quantify analytes under off-gas condensate conditions. The work completed under this project makes timely use of available samples and equipment at PNNL. The project utilized the opportunity to collect off-gas samples from planned AP-105 processing work and included the direct condensate and the evaporate from the DFLAW Radioactive Waste Test Platform. Samples were characterized by instruments already in place at PNNL including a Raman spectrometer optimized for in-line monitoring of flowing and stationary samples as well as a LIBS instrument, which was optimized for static liquid droplet analysis. The ultimate objective was to determine if these techniques could be used to qualitatively characterize analytes present within the off-gas samples. The testing confirmed the use of the Raman as an in-line monitoring system was able to qualitatively observe NO 3 - , NO 2 - , aluminum (as aluminate, Al(OH) 4 - ), SO 4 2- , CrO 4 2- , CO 3 2- , and PO 4 3- in the AP-105 melter feed evaporator condensate samples. The testing also confirmed LIBS as a potential useful technique for in-line monitoring, able to qualitatively detect Na, N, Al, and tentatively Cr and Cl in a simulant stock evaporate solution.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2022

National Smart Manufacturing Strategic Plan: To Facilitate More Rapid Development, Deployment and Adoption of Smart Manufacturing Technologies

Smart manufacturing technologies provide real-time data and insight to improve the productivity, efficiency, and competitiveness of U.S. manufacturing, creating the potential for new jobs in the manufacturing sector. These technologies can support U.S. manufacturers’ ability to increase throughput and energy efficiency, and decrease waste, defects, and costs. A wide range of manufacturing and industrial subsectors, particularly energy-intensive and energy-dependent industries, have the potential to benefit from smart manufacturing technologies. There are technical improvements still needed to reduce the costs and barriers (trained workforce and upskilling, software-hardware integration, cost, and technical barriers to deployment of advanced sensors, computing, and communication technologies for existing manufacturing assets) to the adoption of smart manufacturing technologies, especially to small and medium-sized manufacturers, and subsequently, increase the overall adoption rate of smart manufacturing technologies. This report outlines the Department of Energy’s (DOE) strategic plan to accelerate the development and implementation of smart manufacturing technologies in the United States and the actions DOE has taken to use these technologies in smart manufacturing for the United States. DOE’s plan to facilitate more rapid development, deployment and widespread adoption of smart manufacturing technologies derive from the 2018 Strategy for American Leadership in Advanced Manufacturing. The strategy outlines a vision for America’s leadership in advanced manufacturing including the development of intelligent manufacturing systems to optimize manufacturing facilities and support the manufacturing of transformative materials. DOE’s Clean Energy Smart Manufacturing Innovation Institute (CESMII), a Manufacturing USA Institute, focuses on accelerating the development and adoption of advanced sensors, controls, platforms, and models needed for smart manufacturing. The objective is to enhance U.S. manufacturing productivity and global competitiveness through the research and development of these technologies. Smart manufacturing has the potential to improve the overall performance, energy productivity, and efficiency of manufacturing, fostering the economic competitiveness of the manufacturing sector.

99 GENERAL AND MISCELLANEOUS↗
DOE OSTI2024

Lab Collaboration Project (LCP) for Marine Energy: Quantifying Collision Risk for Fish and Turbines Final Technical Report (Task 10)

A persistent environmental concern for the widespread deployment of tidal turbines is the potential for fish and marine mammals to collide with rotating blades (Copping et al. 2016, Copping and Hemery 2020). This is a consequence of well-documented bird and bat mortalities around wind turbines (Smallwood 2007, Thompson et al. 2017), as well as fish mortality at conventional hydropower dams (Pracheil et al. 2016) and tidal barrages (Dadswell and Rulifson 1994). However, unlike hydropower dams or barrages, tidal turbines do not involve structures that channel all flow through the turbines. Similarly, while functionally similar to wind turbines, tidal turbines often operate at lower relative velocities and, depending on the end-use application, may be significantly smaller than utility-scale wind turbines. Both of these factors reduce the likelihood and severity of collision, but the knowledge base on this topic remains limited.

13 HYDRO ENERGY↗
DOE OSTI2026

Desert-Urban System Integrated Atmospheric Monsoon (DUSTIEAIM) in the Southwestern United States Science Plan

The Desert-Urban System Integrated Atmospheric Monsoon (DUSTIEAIM) campaign is a groundbreaking, high-impact scientific mission that will transform how we understand and respond to energy and water challenges in one of America’s fastest-growing and most heat-stressed urban regions: Phoenix, Arizona. Starting in April 2026, this 18-month field campaign harnesses the full power of the U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) user facility and an interdisciplinary science team including national laboratories, universities, and agencies with a broad range of subject-matter expertise. With cutting-edge instruments, active and passive ground-based sensors, radars, and integrated modeling, DUSTIEAIM will deliver the most comprehensive environmental data set ever collected for a desert-urban-agricultural interface.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2021

Active Optical Control with Machine Learning: A Proof of Concept for the Vera C. Rubin Observatory

Abstract The Active Optics System of the Vera C. Rubin Observatory (Rubin) uses information provided by four wave front sensors to determine deviations between the reconstructed wave front and the ideal wave front. The observed deviations are used to adjust the control parameters of the optical system to maintain image quality across the 3.°5 field of view. The baseline approach from the project is to obtain amplitudes of the Zernike polynomials describing the distorted wave front from out-of-focus images collected by the wave front sensors. These Zernike amplitudes are related via an “influence matrix” to the control parameters necessary to correct the wave front. In this paper, we use deep-learning methods to extract the control parameters directly from the images captured by the wave front sensors. Our neural net model uses anti-aliasing pooling to boost performance, and a domain-specific loss function to aid learning and generalization. The accuracy of the control parameters derived from our model exceeds Rubin requirements even in the presence of full-moon background levels and mis-centering of reference stars. Although the training process is time consuming, model evaluation requires only a few milliseconds. This low latency should allow for the correction of the optical configuration during the readout and slew interval between successive exposures.

Astronomy & Astrophysics↗
NASA NTRS1974

Skylab contamination control

The optical contamination control systems of Skylab are reviewed, covering contamination sources, critical elements, flight hardware configuration, contamination monitoring sensors, mathematical contamination prediction models, contamination cloud and deposition models, and hardware implementation. Also considered are supportive contamination tests, contamination mission support activities, Skylab contamination evaluation, contamination measurement experiments, and the effectiveness of contamination control measures. Sources of contamination are identified, Skylab system susceptibility to contamination is determined, and predictions are made for surface contamination deposition and background brightness levels. Mission evaluation results indicate that, barring anomalous conditions, Skylab mission equipment and activities are adequate to reduce the general contamination level to the sensitivity threshold levels for experiments and affected subsystems.

Davis, C. M.↗
NASA NTRS1977

Monitoring Air Pollution from Satellites (MAPS). Volume 1: Technical report

Performance tests on an electro-optical model of an infrared sensor for remote measurements of trace atmospheric gases are detailed; the instrument utilized a sample of the gas to be measured as spectral filter. Also reported is the development of radiometric calibration equipment that determines responses to simulated pollution effects. Results show excellent agreement with theoretical performance predictions with the exception of nonuniform radiance responses. Balance stability to an accuracy better than the rms noise level was demonstrated for the EOM in both the NH3 and CO modes for a period of two days under laboratory conditions. Flight test results show that the temperature range of the absorption cell is restricted to 255 K or higher.

Source record↗
NASA NTRS1978

Infrared scanners for temperature measurement in wind tunnels

Remote infrared scanners allow large surfaces to be studied without disturbing model and without extensive sensor installation. Computer techniques analyze data with accuracy of + or - 5 percent. Scanners are applicable to tracking and diffusion studies of rocket exhausts, nondestructive testing of rocket motor nozzles and composite materials, and detection of nonuniformity in home insulation.

Kantsios, A. G.↗
NASA NTRS1985

Operational MTF for Landsat Thematic Mapper

The Landsat Thematic Mapper (TM) represents significant improvements in spatial, spectral, and radiometric resolution over the older Multispectral Scanner System (MSS). For the last three years, NASA has conducted the Landsat Image Data Quality Analysis (LIDQA) program to quantify the performance of the TM on the Landsat-4 and 5 spacecraft. As part of this program, analysis of the TM imagery to extract the overall system modulation transfer function (MTF) has been performed. In this paper, the San Mateo Bridge in San Francisco is described as a target for calculation of the line spread function and MTF. The analysis of two TM scenes, one from 12/31/82 and one from 8/12/83, yielded effective-instantaneous-field-of-views (EIFOVs) of 40.8 meters and 48.6 meters, respectively. These values are compared with the 33.8 meter EIFOV predicted by component modelling of the TM sensor, and the differences discussed.

Schowengerdt, R.↗
NASA NTRS1989

Spacecraft attitude determination using the earth's magnetic field

A method is presented by which the attitude of a low-Earth orbiting spacecraft may be determined using a vector magnetometer, a digital Sun sensor, and a mathematical model of the Earth's magnetic field. The method is currently being implemented for the Solar Maximum Mission spacecraft (as a backup for the failing star trackers) as a way to determine roll gyro drift.

Simpson, David G.↗
NASA NTRS1990

Feasibility of using Extreme Ultraviolet Explorer (EUVE) reaction wheels to satisfy Space Infrared Telescope Facility (SIRTF) maneuver requirements

A digital computer simulation is used to determine if the extreme ultraviolet explorer (EUVE) reaction wheels can provide sufficient torque and momentum storage capability to meet the space infrared telescope facility (SIRTF) maneuver requirements. A brief description of the pointing control system (PCS) and the sensor and actuator dynamic models used in the simulation is presented. A model to represent a disturbance such as fluid sloshing is developed. Results developed with the simulation, and a discussion of these results are presented.

Lightsey, W. D.↗
NASA NTRS1989

PACOSS program status and results

Future large space systems (LSS), both civilian and military, will have performance objectives which require stringent pointing accuracies, relatively fast retargeting times, short settling times, accurate dynamic shape requirements, or combinations thereof. Many of these structures will be large but lightweight and will exhibit a dense, low-frequency modal spectrum with significant content within the control bandwidth. Although it is possible in principle to achieve structural vibration control with purely active means, experience with complex structures has shown that the realities of plant model inaccuracies and real sensor and actuator dynamics frequently combine to produce disappointing results. It was shown that a combination of passive and active control will result in a simpler system which can be expected to be more reliable and less expensive than a corresponding system utilizing active control exclusively. The goals of the Passive and Active Control of Space Structures (PACOSS) program consist of a thorough investigation of the relative roles of passive active vibration control, and the development of validated means of vibration control. The program approach, representative system article, dynamic test article, and test status and results are outlined.

Richards, K. E., Jr.↗
NASA NTRS1990

Rain estimation from satellites - Effect of finite field of view

The bias in the rain estimation from satellites, associated with nonuniformly filled FOVs of spaceborne microwave sensors, were estimated using radar data collected during the GARP Atlantic Tropical Experiment. An approximate formula is derived which shows that this bias is closely related to the variance of rain rate within the FOV of the sensor. By applying simple models of rain field to the formula, it is shown that the formula is consistent with the variation of bias.

Chiu, Long S.↗
NASA NTRS1990

A semiempirical model for interpreting microwave emission from semiarid land surfaces as seen from space

A radiative-transfer model for simulating microwave brightness temperatures over land surfaces is described. The model takes into account sensor viewing conditions (spacecraft altitude, viewing angle, frequency, and polarization) and atmospheric parameters over a soil surface characterized by its moisture, roughness, and temperature and covered with a layer of vegetation characterized by its temperature, water content, single scattering albedo, structure, and percent coverage. In order to reduce the influence of atmospheric and surface temperature effects, the brightness temperatures are expressed as polarization ratios that depend primarily on the soil moisture and roughness, canopy water content, and percentage of cover. The sensitivity of the polarization ratio to these parameters is investigated. Simulation of the temporal evolution of the microwave signal over semiarid areas in the African Sahel is presented and compared to actual satellite data from the SMMR instrument on Nimbus-7.

Kerr, Yann H.↗
NASA NTRS1991

Diagnostic reasoning techniques for selective monitoring

An architecture for using diagnostic reasoning techniques in selective monitoring is presented. Given the sensor readings and a model of the physical system, a number of assertions are generated and expressed as Boolean equations. The resulting system of Boolean equations is solved symbolically. Using a priori probabilities of component failure and Bayes' rule, revised probabilities of failure can be computed. These will indicate what components have failed or are the most likely to have failed. This approach is suitable for systems that are well understood and for which the correctness of the assertions can be guaranteed. Also, the system must be such that changes are slow enough to allow the computation.

Homem-De-mello, L. S.↗
NASA NTRS1989

Electro-optic architecture for servicing sensors and actuators in advanced aircraft propulsion systems

A detailed design of a fiber optic propulsion control system, integrating favored sensors and electro-optics architecture is presented. Layouts, schematics, and sensor lists describe an advanced fighter engine system model. Components and attributes of candidate fiber optic sensors are identified, and evaluation criteria are used in a trade study resulting in favored sensors for each measurand. System architectural ground rules were applied to accomplish an electro-optics architecture for the favored sensors. A key result was a considerable reduction in signal conductors. Drawings, schematics, specifications, and printed circuit board layouts describe the detailed system design, including application of a planar optical waveguide interface.

Poppel, G. L.↗
NASA NTRS1992

Rain rate instrument for deployment at sea, phase 2

This report describes, in detail, the SBIR Phase 2 contracting effort provided for by NASA Contract Number NAS8-38481 in which a prototype Rain Rate Sensor was developed. FWG Model RP101A is a fully functional rain rate and droplet size analyzing instrument. The RP101A is a fully functional rain rate and droplet size analyzing instrument. The RP101A consists of a fiber optic probe containing a 32-fiber array connected to an electronic signal processor. When interfaced to an IBM compatible personal computer and configured with appropriate software, the RP101A is capable of measuring rain rates and particles ranging in size from around 300 microns up to 6 to 7 millimeters. FWG Associates, Inc. intends to develop a production model from the prototype and continue the effort under NASA's SBIR Phase 3 program.

Steele, Jimmy W.↗